The invention relates to a method of producing molten pig iron or steel pre-material from iron-oxide-containing raw-material particles, in particular pre-reduced iron ore, in which the iron-oxide-containing raw-material particles are top-charged into a fluidized bed comprised of carbon particles and an oxygen-containing carrier gas and are heated, reduced and smelted when passing through the same, as well as to a plant for carrying out the method.
With the methods of this kind known so far, a high input of energy is necessary, with the utilization of the energy not being regarded as optimal, so that the heat balance and thus the economy of the known methods have not been satisfactory. Furthermore, it is not possible with the known methods to maintain the fluidized bed in a vessel of a great diameter. Therefore, one is all the more bound to relatively small vessels of little diameter, which is also not economical.
The charging of the oxygen-containing carrier gas has to be effected closely above the surface of the slag bath in order that the fluidized bed reaches up to this surface. With the known methods, this results in the formation of a zone of maximum temperature of the fluidized bed (high-temperature zone) in the lower region of the fluidized bed, i.e., closely above the slag bath surface. This has the disadvantage that in this zone a reoxidation of the iron-ore particles already reduced completely cannot be safely prevented.